Suzi Catchpole

How a mum gives birth to a 5.755kg (12lb 6oz) baby without pain relief will be beyond the comprehension of many, but that's exactly what happened when Nikki Bell welcomed son Parker on November 1.

And it's not the only remarkable thing about Parker, with the baby boy breaking Blacktown Hospital's baby weight record for a natural birth.

Described as a "gorgeous chunky boy", the new arrival is settling in well with his family, mum Nikki, 28, dad Michael, 30, and big sister Maddison, 20 months, at their home in Riverstone in Sydney's west.

Blacktown Midwifery Group announced the record birth on its Facebook page, reporting "the not-so-little Parker and mum Nikki are doing well," and that Parker will "be the talk of Blacktown Maternity for a long time to come."

The family told News.com.au they were aware he was going to be a big baby after his estimated weight at the 24 week scan was about 3.5kg, which is about the current national average for a newborn full-term baby. Parker arrived at 39 weeks and three days, after 2.5 hours of labour.

Nikki said, "My first baby went until 41 weeks and 3 days - lucky I didn't go that far he would have been 6kg plus," adding that birth hurts no matter the size of the baby.

The Blacktown Midwifery Group's post has attracted 3100 comments and more than 1080 shares, with many remarking that Parker looks bigger than much older babies.